Locking switch



Aug. "251, 1923.'

LOCKING SWITCH Filed Feb. 11 1922 resident of Boston, `in

Patented Aug., 2l, i923.

unir; stairs earner RiJDoLPH ir. MARrENs-,or Bos'rori, MASSACHUSETTS. j i

Applicationrled February 11, 1922. Serial No. 535,769.

:usual-lyattachedto a` walland sometimes to -a ceiling and the opening and closing ofthe switch is then customarily effectedby means of a pole having alhook to engagethe movable member of the switch to pull that memberopen or to swing it back to closethe circuit'.- Tofavoid. liabilityof the switch accidentally opening, due to the effect of gravity or for other reasons, the movable members or` blades of such switches have been provided with hooks pivoted thereto and adapted to engage fixed catch lugs to hold the blades-in circuit closing positions. Some objections to the pivoted hooks have been raised on the ground that the pivots are not always capable of withstanding the strain after long continued use. If the pivot of one of such switches should give way, or Slip from place, nothing is left to prevent the the switch from accidentally opening.

The object of the present invention is to provide Switches of the general type described with simple and positive locking devices which will reliably prevent accidental opening of the switch blades even after long continued use with' resultant wear.

lith this object in view my invention consists in the improvement which I shall Vnow proceed to describe and claim.

Of the accompanying drawings,

Figure 1 is aside elevation of a wellknown form of single throw switch having my improvements applied thereto.

Figure 2 represents an elevation lookingV from the right of Figure 1.

. Figure 3 represents a section on line 3-3 of Figure 1 on a larger scale.

Similar reference characters indicate similar parts in all of the views.

Two insulating posts 12, 12, connectedA to a suitable base 13 are provided with cap members 14: 15 for the connection of the usual circuit wires, said members 14, 15,

being provided respectively with switch jaws 16, 17. The movable member of the s witchl held in the relative l'sults j in opening the iaeaaei eerie@ LOCKING SWITCH.` L

.manufactura made in two parts as indicated in Figures 2 and 3, the parts being positions indicated by the screws or rivets which pass through the end of the blade 18 and by such additional screws or rivets as may be desired. Said two parts of the housing are formed with openings to provide an eye 23 which is also in line with the blade (Fig. 1) for a purpose presently described.

A short bolt 24 is mounted to slide in the housing close to and parallel with the edge of the blade toward or from the recess behind the keeper lug 21, said bolt having an aperture or small recess into which projects the tip 25 of a lever 26 pivoted at 27 in the housing and having a curved end 28 which overlaps the eye 23 and is curved to a shorter radius than the radius of the inner circle of the said eye.

A1 spring 29 is confined between the lever 26 and a screw plug 30 mounted in the housing, said spring exerting a pressure to cause the tip of the lever to hold the bolt 24.- in the .loc-king position indicated in Figure 1 when and while the switch blade is in circuit-closing position. Fgure 1 is partially broken out to better illustrate the parts just referred to. Asshown in said gure one side of the bolt is bevelled to enable it to ride over the lug 21 when the switch is being closed.

vVihen the switch is to be opened from the position shown in Figure 1, the user simply pivot so that its tip 25 withdraws the bolt 24 from behind the keeper lug 21, as indicatedv by dotted lines in Figure 1. tinued pull, owing to the implement then engaging the inner surface of the eye, re-

switch. Any pushing action to swing the switch blade in the re- Conico

ein

turn direction causes the bolt to automatically re-engage the-keeper lug the spring 29 yielding when the bevelled surfacev of, the;

bolt contacts with the keeper lug.v

As the eye 23 in the housing, and the 5 curved end 28 of the lever, are substantially in line with the mid-length of the blade, neither a pulling nor a pushingl action causes any twisting action on the blade.

The pivot-Q'hasnothing tok do with holding'the` switch in locked. position and therer the keeper lug;

A further advantage-resulting from the present structure is that the switch can not be accidentally thrown open even if subjected'to a severe shock due to a short cir- Cult;

I; do not limit myself to the-employment of my improved locking mechanism in connection with single'fthrow switches, as the same may be applied to the type knowniasdouble throw switches. i s

Having now described. my invention,V I claim:

Y l. A device of the character described,A

having a pivoted switch blade, an extension projecting: beyondthe end .foi theblade in line therewith, a* lever pivoted to said extension,` a bolt in, engagement with said lever :and mounted to slide parallel; with the edge of; theblade, aV switch :jawxto cooperate with the blade, and aboltkeeper ad] a-cent to the base ofsaid switch jaw.

2. An electricA switch having a circuit-cony trolling blade pivoted at one end and having a housing providedwith an neye'beyond the otherend of the blade in line therewith,

a boltgmounted to slide in-'a direction substantially parallel with and` in the-plane of one edge of therblade,l a; lever'mountedin the-'housing and engaging. the bolt and'crossing the spacewithir'i the eye oli-the housing,

and aiiixed'keeper for said` bolt;

In testimonyl whereof have; aliXedA my Signature.

RUDOLPH M@ MARTENS. 

